As commercial integrated circuits push into 90-nm process technology with 50-nm gates and research devices push even smaller, further improvements in performance by scaling the channel length of transistors appear to be approaching the limits of scaling due to short channel, gate current leakage, and other effects. In particular, the power dissipation of integrated circuits is increasingly a problem as the transistor channel length is scaled down and transistors can no longer be completely shut off. Indeed the resulting increases in the off-state leakage current degrade the on-off current ratio. There are also short channel effects such as punch through and three dimensional effects that result from fringing and corners. Some researchers have suggested that the end to Moore's law, which has described the progression of silicon integrated circuit technology, is near. Others have suggested that entirely new technologies such as molecular electronics and carbon nanotube transistors are needed to prevent a slowdown in the improvement of electronics.